Return air blocking device for fan-based heat dissipation mechanism

ABSTRACT

A return air blocking device for a fan-based heat dissipation mechanism includes a plurality of rotatable hinged plates provided in a heat-dissipation mechanism having a plurality of fans. The rotatable hinged plates are lifted open or shut due to the presence or absence of airflow kinetic energy. When some of the fans fail, the corresponding rotatable hinged plates are shut to prevent hot exhaust from returning to and being detained in the heat dissipation mechanism.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to fan-based heat dissipation mechanisms and, more particularly, to a return air blocking device for a fan-based heat dissipation mechanism having a plurality of fans, wherein a plurality of rotatable hinged plates are provided on outer sides of the fans and are lifted open or shut by virtue of the kinetic energy of airflow. Thus, when some of the fans fail to function, hot exhaust is prevented from returning to the heat dissipation mechanism and being detained therein, so as not to interfere with the design airflow.

2. Description of Related Art

In order to ensure highly reliable operation, information apparatuses such as industrial servers and computers are generally equipped with a fan-based mechanism including a fan configured for heat dissipation. When the fan works properly, heat dissipation is carried out as designed. However, the fan may fail unexpectedly whenever its service life comes to an end.

Hence, an information apparatus for industrial use typically has at least two cooling fans for backup purpose. Nevertheless, when one of the fans malfunctions (given a low chance of simultaneous breakdown of several fans), the airflow path in the apparatus will be adversely changed so that the intended heat dissipating effect is unattainable.

The aforesaid change of airflow path occurs because the malfunctioning fan is located at an air outlet important for heat dissipation. Once the fan stops operating, no hot air or exhaust will be discharged through the fan, thus turning the air outlet, which is usually adjacent to the other fan(s), into an air inlet for the immediately adjacent functioning fan(s). As a result, heat dissipation efficiency decreases significantly.

BRIEF SUMMARY OF THE INVENTION

According to the present invention, a return air blocking device includes rotatable hinged plates installed at air outlets of cooling fans. When the fans are not in operation, the rotatable hinged plates are shut under the action of gravity. When the fans are actuated, air blown outward by the fans will rotate and lift the rotatable hinged plates up to allow passage of airflow.

Should one of the fans fail, the corresponding air outlet will be turned into an air inlet, and the corresponding rotatable hinged plate will be automatically shut by the incoming airflow in addition to gravity, thus blocking the now air inlet which might otherwise allow hot exhaust to return and interfere with heat dissipation.

Now that the factor causing the change of airflow path is eliminated, all the other functioning fans are allowed to maintain their intended operation, at deteriorated efficiency of heat dissipation, though. In so doing, hot exhaust is prevented from returning and being detained, so as not to interfere with the otherwise fluent heat-dissipating airflow.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The invention as well as a preferred mode of use, further objectives, and advantages thereof will be best understood by referring to the following detailed description of illustrative embodiments in conjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of an embodiment of the present invention;

FIG. 2 is a perspective view of another embodiment of the present invention; and

FIG. 3 is an exploded perspective view of the embodiment shown in FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a return air blocking device for a fan-based heat dissipation mechanism according to the present invention includes a plurality of rotatable hinged plates 13, 14, 15, 16, 17, 18 which are installed at outer sides of a plurality of air outlets 11, 12 of a chassis 1 and correspond in position to a plurality of fans mounted in the chassis 1.

When the fans in the chassis 1 work normally and blow out air, the rotatable hinged plates 13, 14, 15, 16, 17, 18 are rotated and lifted open by the kinetic energy of airflow driven by the fans, thus allowing hot exhaust to be discharged. When one of the fans, such as the one corresponding in position to the rotatable hinged plates 17, 18, fails, the rotatable hinged plates 17, 18 drop automatically and are thus shut due to gravity and absence of the airflow kinetic energy. In consequence, external air or hot exhaust discharged from the neighboring fan is prevented from being sucked into and detained in the chassis 1, which might otherwise result in obstruction of the heat-dissipating airflow.

Referring to FIG. 2 and FIG. 3, the return air blocking device for a fan-based hear dissipation mechanism according to the present invention is implemented as one or several rotatable hinged plates 13, 14 installed at an air outlet 21 of a fan frame 2 configured for receiving a blower fan 22 mounted securely therein. After the mounting of the blower fan 22 in the fan frame 2 and the installation of the rotatable hinged plates 13, 14 at the air outlet 21 of the fan frame 2, the fan frame 2 can be conveniently installed on the chassis 1 for use. 

1. A return air blocking device for a fan-based heat dissipation mechanism, essentially comprising a plurality of rotatable hinged plates provided at outer sides of a plurality of air outlets of a chassis such that the rotatable hinged plates correspond in position to a plurality of fans mounted in the chassis, wherein when all the fans in the chassis are in normal operation, all the rotatable hinged plates are rotated and thus lifted open by kinetic energy of airflow driven by the fans, wherein when one of the fans fails, at least a corresponding one of the rotatable hinged plates drops automatically due to gravity so as to be shut, thereby preventing external air or hot exhaust discharged via a neighboring said fan from being sucked into the chassis.
 2. The return air blocking device of claim 1, wherein at least one of the rotatable hinged plates is provided at an air outlet of a fan frame configured for receiving a blower fan mounted securely in the fan frame, and the fan frame which is mounted securely with the blower fan and whose said air outlet is provided with the at least one rotatable hinged plate is conveniently installed on the chassis. 